Automatic train brake control



2 Sheets-Sheet l'.

May 23, 1939. c.y c. FARMER l AUTOMATIC TRAIN BRAKE CONTROL Filed June 18, 1957 w: TE @NQS o: NQ Q .v2

May 23, 1939. c. c. FARMER AUTOMATIC TRAIN BRAKE CONTROL 2 She'ets-Sheet 2 Filed June 18, 1937 EMERGENCY SERVICE FIRST RUNNING sERvIcE LAP w E L m l Il Jg.. 2. FIRST 4 RUNNING SERVICE- LAP SERVICE EMERGENCY IDG 104 l |NVENTOR- CLYDEQHARMER 1E%r/ el ,OQ

RUNNlNG I 7o |71 ale- BQIRST SERVICE I q 22 223-. I `LAR SERVICE ErmE'Rfsl-:Ncr`

I CIE ATTORNEY i y of,` generally at a full service rate.

`equipment', the engineer may, by acting within Patented May 23, 1939 PATENT OFFICE 2,159,789 *AUTOMATIC TRAIN BRAKE CONTROL Clyde C. Farmer, Pittsburgh, Pa., assignor to The `Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application June 18, 1937, Serial No. 148,945

` 32 Claims.

, 'I'his invention relates to train control apparatus of the type automatically operative in response to track signals for controlling the air brakes on a railway train, and particularly to n 'kzsautomatic train control equipment having means associated therewith for permitting the engineer to `retain control of the application of the brakes by `acting as required promptly in response to an i unfavorable traffic signal.V

101i4 Train control apparatus has heretofore been proposed which is automatically set in operation after a necessarily short interval, usually about q "six seconds, following communication of an unfavorable traiic signal, to take complete control 15 ,-fof `the brakes and to effect an application there- With such theiallowed interval to effect an application vof thelbrakes by the `usual operation of the brake 20 valve, suppress the automatic operation of the train control apparatus, and thus retain control of the brakes. Occasionally, however, the engineer of a train may fail to perform the required l .act in response to a danger signal in time to suppress an automatic train control application,

due to inadvertence or other cause such as, possibly, a faulty operation of the signal responsive timing mechanism included with the train control apparatus.

If the engineer thus fails to act in time to suppress the automatic operation of the train conq trol apparatus, the train` control apparatus then effects a full service application automatically. wWhen the train control apparatus of the above `type is once set in operation as Vjust explained, control of the application of the brakes is thus taken from the engineer, who can thereafterdo nothing to regulate the rate at which the application is effected, although he can usually move `the brake valveto lap position to prevent complete loss of brake pipe pressure,

It is well known,l however, that in orderto prevent dan-gerous slack action in a train, the rate and manner of effecting a service application of the brakes should be controlled in accordance with the conditions of service, such as thelength of the train Vand the degree of brake pipe leakage. On a long train, for example,` it is desirable "rstto eiect a light application of the brakes in order to cause' gentle gathering of the slack between the cars, after which a second stage application of greater degree may be effected with safety. Since a train control equipment is priq marily a safety device and is thus adapted to 55 ,function for applying the brakes only under exceptional circumstances, it is generally not desirable to provide in addition complicated and expensive mechanism designed to govern the rate of effecting automatic application of the'brakes in accordance with varying service conditions. On the other hand, there are obvious advantages to be gained in employing, with a train control apparatus, a manually operated braking equipment of the type designed to permit the desired exible control of the brakes on trains under various service conditions, such as the well known No. 8 ET air brake equipment, together with means permitting the manually operated equipment to be rendered effective to control the rate at which the brakes are applied even after the train control apparatus has been set in operation. l

One objectv of my invention is to provide" an improved train control equipment embodying the above advantages.

Another object of my 4invention is to provide `an improved train control equipment having means adapted to respond to operation of a brake valve, after operation of the train control mechanism has begun, to check the automatic reduction in brake pipe pressure for permitting a split l or two stage reduction to be effected by the engineer.

A further object of my invention is to provide an automatic train brake control equipment having a suppression feature for permitting the engineer to prevent operation of the equipment to effect a train control application of the brakes by performing a required act in response to an adverse signal indication, and having in addition a recapture mechanism adapted to be operated through the medium of the brake valve, immediately after an automatic reduction in brake pipe pressure has been initiated by the train control equipment, to enable the engineer to regain control of the brakes for completing the brake application.

A still further object is to provide improved automatic brake control equipment including a recapture mechanism operative to permit manual control of a reduction. in brake pipe pressure initiated automatically, which equipment is adapted to be employed with existing standard train brake and signal equipment.

Other objects and advantages will appear in the following more detailed description of my invention, taken in connection with the accompanying drawings wherein:

Fig. 1 is a diagrammatic sectional view of a train control equipment embodying my invention;

Figs. 2 and 3 are diagrammatic development y views showing the port connections established in different positions of the upper and lower rotary valves, respectively, of the brake valve device shown in Fig. 1;

Fig. 4 is a diagrammatic sectional view of the application slide valve portion of the train control equipment shown in application position; and

Fig. 5 is a fragmentary plan view of the engineers brake valve device illustrating different positions thereof.

Referring to Fig. 1 of the drawings, there is provided an engineers brake valve device I, a pipe bracket 2, to which the brake valve device is secured, a brake pipe 3, a casing section 4 secured to the pipe bracket 2 and containing the recapture valve and application valve mechanisms, respectively, another casing section comprising a suppression valve portion 9 and a reduction ensuring valve portion I9, a timing valve device II, and a magnet valve device I2.

As shown in the drawings, the timing valve device I I and the magnet valve device I2 may be embodied in a unitary structure, and are adapted to cooperate in response to changes in traffic signal indications for initiating operation of the train control apparatus after the lapse of a predetermined interval. The magnet valve device I2 comprises a supply valve I4 mounted ina valve chamber I5 and having a fluted stem I6, a vent valve I1 mounted in a valve chamber I8 and having a fluted stem I9 which operatively engages the stem I6, and a magnet 2|), which, when energized, is adapted to maintain the vent valve I1 seated and the supplyV valve I4 unseated against the pressure of a spring 2l disposed in the chamber I5. 'Ihe magnet 20 may be energized by, current induced from a track signal circuit while trame conditions are favorable, and is adapted to` be deenergized when trame conditions become unfavorable.

The valve chamber I5 in the magnet valve device communicates through a passage 23 with the outletv of a feed valve device 24, the inlet of which is connected through a pipe 22 with the usual main reservoir 25, and which may be of any desired type adapted to supply fluid at a predetermined pressure to the chamber from the main reservoir. The valve chamber I 8 in the magnet valve device communicates by way of a passage 26 and a whistle device 21 with the atymosphere.

The timing valve device II is adapted to be Y governed by the magnet valve device I2 and comprises a casing having a valve chamber 29 containing a double beat valve 39 whichhas a uted stem 3| extending into a chamber 32 and subject to the pressure of 'a spring 33 therein, and which valve also has a stem 35 extending downwardly into a chamber 36. The chamber 36 is open to the atmosphere through a passage 31 and has fslidably mounted therein a valve piston 38, which is normally urged into an upper seated position by the pressure of iiuid in a chamber 39 and in a timing chamber 49 connected thereto. With the valve piston 38 in this position, a spring 42 disposed between the lower wall thereof and the end of the stem 35 is adapted to maintain the double beat valve 30 in its upper seated position for connecting th-e chamber 29 to atmosphere through chamber 36, as shown in the drawings. ;A spring 43 is provided for urging the valvevpiston 38 downwardly in opposition to the fluid pressure in the chamber 39.

The timing valve device II is adapted to function to control the operation of an application valve device in effecting an automatic reduction in pressure of fluid in the brake pipe, and as shown in Fig. 1 of the drawings the chamber 32 in the timing valve device is connected by way of a pipe 44 with a piston chamber 45 formed in the casing section 4 and containing an application piston 46 that is adapted to operate an application slide valve 41 through the medium of a stem 48. The application slide valve 41 is mounted within a valve chamber 50 formed in the casing section 4, and is operative when moved from the normal or release position illustrated in Fig. 1 to an application position to initiate an automatic train control application of the brakes in the manner hereinafter described. A spring 5i is interposed between the application piston 49 and the upper wall of the chamber 45 for urging the piston and the application Vslide valve 41 into the normal position.

Also contained in the casing section 4 is a recapture valve mechanism, which, in accordance with my invention, when operated in the manner hereinafter described functions to check the rate at which an automatic application of the brakes is effected after the application has been initiated by operation of the train control apparatus including the application slide valve 41. YThe recapture valve device comprises a cylindrical valve element 54 slidably mounted in a bore 55 formed in the casing section 4, which valve element has an annular rib 59 adapted for seating engagement with a gasket 51 that is interposed between the casing section 4 and a cover Vplate 4a and is adapted to control communication between the bore 55 and a passage 58, which is connected to a service reduction reservoir 90. A spring 6I is interposed between the valve element 54 and the cover plate 4a for urging the valve element away from the gasket 51. For operating the valve element54 there is provided a valve piston 63 having at one side a pressure chamber G4 and at the other side an atmospheric chamber '65 through which extends a stem 66 which is secured to the valve piston 63 and has its upper end in operating engagement with a sealing disc 68 that is disposed in engagement with the lower side of the valve element 54. The sealing disc 68 is adapted to engage an annular rib 69 formed in the casing section 4 at the uppermost end of the chamber 65, when the valve element 54 is in the unseated position illustrated in Fig. 1 of the drawings.

In the preferred embodiment of my invention disclosed in the drawings, both the suppression valve device 9 and the reduction ensuring valve device II! are provided as a unit in a casing section secured to the casing section 4, although it will be understood that the functions of these devices are distinct. The application suppression valve device 9 is provided as. a means for suppressing or preventing operation of the application slide valve 41 to effect an automatic application of the brakes when the engineer performs a required act in response to an unfavorable traic signal in the manner hereinafter explained, and may comprise a ilexible diaphragm 1I having on one side a diaphragm chamber 12 and on the opposite side a diaphragm chamber 13, which diaphragm is adapted to operate a double beat valve 14 contained in a valve chamber 15, the valve 14 being normally biased toward its upper seated position by aspring "I1.

valve 96 and a lower rotary valve 91, which are y It isa function of the reduction ensuring valve device. I to prevent a complete suppression of `8| and in adiaphragm chamber 82, andv adapted tained in a valve chamber 84 and is normally7 `urged toward its upper seated position by the pressure of a spring 85 disposed inA a chamber f" 86thejvalve 83 in this position being adapted to maintain communication from the valve chamber l 84 through chamber 86 and a restricted exhaust passage 81 to the atmosphere.

`The brake valve device comprises a lowe `casing section 90, an intermediate casing section 9|\,'and an upper casing section 92, the lower cas-` mediate casing section 9| havingformed therein a1 valve chamber 95 containing an upper rotary `adapted' to be operated through the medium of i ing handle |00. so

arotary shaft 99 provided with the usual operat- As is best shown in Fig. the brake valve device I has running, iirst service, lap,` service and emergency positions, it being understood that a full release position might also beprovided if desired.

An exhaust Valve |02 is disposed in` a valve chamber |0|` formed in the upper casing ,section 92 of the brake valve device, and is normally urged into seated position by the force of a spring |03. The exhaust valve |82 has a fluted stem |04 operatively mounted in a suitable bore and y. extending into a chamber |05 which is open to the atmosphere by way of a passagel |06. Mounted i on the shaft 99 is a cam |98 which is engageable with the end of the stem |04 and is operative V to maintain the exhaust valve |02 `in unseated position inall positions of the brake` valve device except running positiomas hereinafter explained. lThe equalizing discharge valve device 93 com- `}prise`s a brake pipe discharge valve H0 adapted` to: control the discharge communication from a chamber `which is connected to the brake pipe 3` by way of a passage H2, said valve being provided with a stem having a collar H4 against which a biasing spring H5 acts for .normally `urging the valve H0 into seated position. The

collar H4 is adapted to be operatively engaged by fone arm ofa bell crank `lever H6 which is pivotally mounted vupon a pin H1 carried by the casing, `the other arm H8 of the bell crank lever i being provided with a rounded end ||8a which lis; operatively disposed.y in a suitable opening formed in the stem of an `equalizing piston H9.

`The equalizing piston H9 is subject on the lower sideyto the pressure of fluid in the chamber IH and on the upper side to the pressure of fluid i in ,a chamber I2I, which communicates by way cfa passage |22 with the usual equalizing reservoir |23. is` also adapted to engage the upper end of a The arm H8 of the bell crank lever stem |24 connected to a maintaining valve |25,

operative to `cutioif the supplyu` of uid `under `wall separating said chambers.

pressure by way of the brake valve device to the brake pipe 3 in the event of operation of the application slide valve 41 and other elements of the train control apparatus to elect an automatic reductionv in brake pipe pressure. The cut off valve mechanism |3|ll comprises a valve |3| contained in a valve chamber |32 and adapted to be operated through the medium oi a stem |33 by a pistonfl 34, which is subject to the opposing pressuresof fluid in a chamber |36 and in a chamber |31 that is connected with the chamber |32 through an opening |38 formed in the The valve |3| is adapted to engage an annular seat |39 surroundingthe opening |38 for cutting off communication between the valve chamber |32 and the chamber |31, and is normally urged away from the seat by the pressure of a spring |40 disposed in the chamber |36 and acting againstthepiston |34.

In operation, uid under pressure supplied in the `usual manner to the main reservoir 25 fiows therefrom by Way of the pipe 22 to the feed valve device 24, which is operative inthe usual manner to supply fluid at reduced pressure through the passage 23 to the valve chamber |5 in the magnet valve device l2. Assuming that the track signal conditions are favorable so that the magnet `2|) is energized for holding the vent valve l1 seated and the supply valve |4 unseated as shown in Fig. 1 of the drawings, fluid under pressure is permitted to ilow past the valve |4 and the fluted stem I6, through a passage |50, past a ball check valve |5I, and through a passage |52 in the timing valve device to the connected chambers 39 and 40. Fluid under pressure in the chamber 39 acts against the valve piston 38 so as to move the valve piston to its upper seated position against the force of the spring 43, thereby causing `the double beat valve 30 to be urged to its upper seated positionas shown in the drawings, wherein communication from the chamber 32 to the valve chamber 29 is` cut off.

Fluid under pressure is also'supplied from the main reservoir 25 by way ot a pipe and passage |54 to the chamber 50 which contains the application slide valve 41, and from the chamber 50 uid under main reservoir pressure is permitted to flow through a restricted port |55 formed in the application piston 46 to the piston chamber 45 and thence by way of pipe 44 to the chamber 32 in the timing valve device H. As the pressure of fluid on opposite sides of the application piston 46 is thus equalized, the spring 5| is permitted to act through the medium of the piston and the stem 48 to maintain the application slide valve 41 in the release position as shown in Fig. 1 of the drawings.

Fluid under pressure is at the same time supplied from the main reservoir 25 through a pipe |51 to a feed valve device |58, which is operative in the usual `manner to supply uid at a reduced pressure through a pipe and passage |59 to the valve chamber `95 in the brake valve devicev With the brake valve device positioned in running position as shown in Fig. 1 of the drawings,-

k ing on both sides of the equalizing piston H9,`

Bil

the maintaining valve |25 in the equalizing discharge valve mechanism 93.

rPhe port |65 in the rotary valve 91 also registers with a passage |68 through which fluid under pressure is supplied to the chamber |32 in the cut off valve device |30. The passage |68 also leads to the seat of thel application slide valve 41, and with the application slide valve in the normal or release position illustrated in Fig. 1 of the drawings, a cavity |10`formed in the slide valve connects the passage |68 with a passage |1| so that uid under pressure is supplied from the rotary valve chamber 95 in the brake valve evice by way of the' communications just described to the chamber |36 on the left-hand side of the piston |34 in the cut off valve mechanism |30.

With the out ofi valve |31 thus maintained unseated by the force of the spring |40 and of the fluid under pressure in the chamber |36 acting on the piston |34, uid under pressure is supplied from the chamber |32 through the opening |38 and the chamber |31 to the brake pipe passage ||2, and thence flows to the chamber in the Vequalizing .discharge valve mechanism 93, and to the brake pipe 3 through which the fluid under pressure is supplied to the brake controlling valve devices, not shown, on cars in the train.

A branch ||2a of the brake pipe passage 2 leads to the diaphragm chamber 82 beneath the diaphragm of the reduction `ensuring valve device I0, and the pressure of the uid thus supplied to the diaphragm chamber with the aid of the spring acts to maintain the double beat valve 83 in its upper seated position as shown in Fig. 1, in which position communication between the chamber 82 and the valve chamber 84 is out oi while the chamber 84 is connected to the atmosphere by way of the chamber 86 and restricted exhaust passage 81.

At the same time, with the brake valve device in the running position as shown in Fig. 1 of the drawings, a port |18 in the rotary valve 91 registers with a passage |19, so that uid 'under pressure is supplied from the chamber through said passage toV a cavity |80 in the application supply valve 41 registering therewith, and thence flows through the passage |22 to the equalizing reservoir |23 and the equalizing piston chamber |2|. It will be understood that fluid at the pressure carried in the brake pip-e 3 is now actwhich is thus permitted to rest in its normal position as shown in Fig. 1 while the spring ||5 holds the discharge valve ||0 seated.

Fluid under pressure supplied from the valve chamber 95 of the brake valve device to the passage |38 as already explained also flows therefrom by way of a branch passage |68a, a

`'cavity |82 in the upper rotary valve 96 and thence through a passage |83 to the diapragm chamber 8| and a suppression reservoir |84 connected thereto, itfbeing understood that the pressure of fluid thus supplied to thediaphragm chamber 8i is no greater than that of the fluid in the chamber 82 beneath the diaphragm 80, so that the spring 85 will continue to hold the double beat valve 83 in the position shown in Fig. l.

At this time it should be noted that the diaphragm chamber 12 above the diaphragm 1| in the suppression valve device 9 'is connected to the valve chamber 84 in the reduction ensuring device by way of a .passage |15 having a restricted portion |16, and also communicates by Way of a passage |86 with a cavity |81 in the upper rotary valve 96 in the brake valve device which registers with an atmospheric exhaust port |88. It will further be noted that the diaphragm chamber 13 beneath the diaphragm 1| is likewise connected to the atmosphere through a restricted port |90, a passage |9|, a branched passage |92 in the application slide valve 41, and an atmospheric exhaust passage |93, it being assumed that, of course, the application slide valve is in the release position shown in Fig. 1. Since the diaphragm chambers 12 and 13 on opposite sid-es vof the diaphragm 1| in the suppression valve device are thus vented to the atmosphere, the spring 11 is permitted to maintain the double beat valve 14 in its upper seated position as shown in Fig. 1, so that the valve chamber 15 in the suppression valve device 9 is open by Way of a chamber |94 and a passage and pipe |95 tothe double beat valve chamber 29 in the timing valve device It should be further noted that, with the brake valve device in running position and the application slide valve 41 in release position as shown in Fig. l of the drawings, the chamber 64 beneathv the recapture piston 63 is connected with the atmosphere by way of a passage |98, the cavity |81 in the upper rotary valve and the exhaust port |88, so that the recapture valve element 54 is maintained unseated by the spring 6|. The service reduction reservoir 60 is thus maintained in communication with the bore 55 and thence through a passage 200, the passage |92 in the application slide valve 41, and the passage |93 with the atmosphere. A restricted portion |92a of the passage |92 at this time registers with a passage 202 which is connected by way of a pipe 202 with a reduction limiting reservoir 203, and which p-assage also communicates through a cavity 205 in the lower rotary valve 91 of the brake valve device with an atmos- I4 into "seated position while unseating the valve I1, whereupon fluid under pressure begins to flow from the connected chambers 39 and 49 in the timing valve device by way of the passage |52, through a restricted passage 2|0, and thence by way of the passage |50, past the valve l1, through the passage 26 and the whistle 'device 21 to the atmosphere. After a predetermined reduction inthe pressure of fluid in the chamber 30, the spring 43 is `enabled to shift the valve piston 38 downwardly, thereby permitting the spring 33 to act through the. medium of the stem 3| to move the double beat valve 30 into its lower seated position.

With the double beat valve 30 in its lower seated position communication is established between the chamber 32 andthe valve chamber 29, and Vassuming that the engineer has failed to act at this time, iiuid under pressure begins to flow from the piston chamber 45 above the ap plication valve piston 46 through the pipe 44, chamber 32, past the valve 30, through chamber 29, pipe and passage |95, chamber |94,'past the double beat valve 14 to the valve chamber 15 of the suppression valve fdevic'e, and thence through i X u im the usual.

` a passage 2| I. toa stop reservoir 2|2. Fluid under pressure is thus vented from the piston Vchamber 45 at a faster ratethan that of flow i thereto'of `fluid from chamber 50 through the `a5 `restricted passage |55 in the piston, and when `the pressure in the chamber 45 has been reduced suiilciently below that in the valve chamber 50, @the piston 46 and application slide valvel 41 are shifted upwardly into application position.

1". With the application slide valve 41 in Aapplication position, as is shown in Figpi of the drawings, the passage |1| is connected to the exhaust a `passage |02 in the slide valve, so that fluid under pressure is vented from the chamber |36 in *15 the brake pipe cut off Valve device |30,` the "fluid under pressure flowing from the (chamber .through the passage |1|,V passage |92 and passage |93 to the atmosphere. Upon the reduction in the pressure of uid in the chamber |36 the uid pressure in the chamber |31 at the lopposite side of the piston |34 causes the piston to move the valve |3| against the seat |39, thereby preventing further supply of fluid under pressure to the brake pipe.

When the application slide valve 41 is moved to application position, a passage 2|4 formed .therein, which has a restricted portion 2|4a, establishes communication between the passage |22 and passages 200 and 202, with the result `g() that uid under pressure is permitted to flow from the equalizing reservoir |23 and the equalizing piston chamber |2| through the passage "1|22,slide valve passage 2|4, and thence through passages 200 and 202 to the service reduction .1oreservoir 60 and reduction limiting reservoir 203,

` respectively. o It will be understood, of course, that the pasy sage 200 at this time communicates by way of the bore 55 and the passage 58 with the service reduction reservoir 60, since the valve element l 55 is in the unseated position shown in Fig. 1 of the drawings. a Y

As the pressure of fiuid in the equalizing piston l chamber |2| is reduced by flow into the reser- 145 `voirs 60 and 203 as just described, the fluid pressure in the chamber I forces the equalizing piston upwardly, thereby causing the piston to operate the bell crank lever ||6 tounseat `the brake pipe discharge valve H0. Withthe 50 discharge valve` ||0 unseated, fluid under pressure is vented from the brake pipe 3 by way of passage H2, the chamber past the discharge valve Id, through a passage 2|`6 having a restricted portion 2|1, and thence through the ap- 55 plication slide valve passage |82, and the atmospheric exhaust passage |93.v Asalready explained, the` fluid pressure in the equalizing pis- V ton `chamber |2| is at this time permitted to `equalize with the initially atmospheric pressure in both the service reduction reservoir 60 and the lreduction limiting reservoir 203, the comi fbined capacities of which are such that the consequent reduction in uid pressure'` in the cham.-

"i `ber |21l causes operation of the `equalizing dis- 1fly-,charge valve mechanism 93 to vent fluid under pressure from the brake pipe at a service rate. When the pressure of fluid in the `brake pipe 3 hasbeen thus reduced by automatic operation of the train control appartus as just described, brake controlling valve devices .a `throughout the train are operated in the well `known manner to effect `a service application of the brakes. l

while the application slide valve device 411s glinwappiioauoo position as illustrated in Fig. 4.

of the drawings for effecting the automatic servive application of thebrakes inthe manner just described, iiuid under pressure is supplied from the valve chamber 50 by way of the passage |9| and past a ball check valve 220 to the diaphragm chamber 13 in thesuppression valve device 9, thereby insuring against movement of the double beat valve 14 out of the position shown in Figfl. It will also be noted that with the application slide valve 41 in application position, the piston chamber 45 is connected by way of a passage 522i, a cavity 223 in the slide valve, and a 225 with the atmospheric exhaust cavity |81 inthe upper rotary valve 96 in the brake valve device which is still in running position as shown in Fig. l. The stop reservoir 2|2 is likewise connected to the atmosphere by way of the passage 2| l, past a ball check valve 225, and through the passage 224.

It will thus be seen that ifthe brake valve device remains in running position, theapplication piston chamber 45 is vented to atmosphere and the application slide valve 42 is consequently held in its application position, thereby permitting continued flow of fluid under pressure from the equalizing piston chamber |2| to the atmosphere, after equalization into reduction reservoirs 60 and 203, by way of the communications hereinoefore pointed out including the passage 202, the cavity 205 in the rotary valve 91, and the exhaust port' 200. This would result in the brake pipe pressure being reduced to atmospheric pressure, which is unnecessary in eiecting a service application of the brakes. l

In order to prevent complete discharge of fluid 35 paratus has been begun. With the brake valve device in lap position, the passage 202 communicating with the reduction limiting reservoir 203 is lapped, while the atmospheric communication from the passage 224 communicating with the stop reservoir 2 2 is similarly cut oif, so that after the pressures of fluid in the application piston chamber and in the stop reservoir 2|2 have equalized, further ow of fluid from said piston chamber is prevented. Continued flow of fluid under pressure from the valve chamber through the restricted port in the applicationpiston 45 then causes the fluid pressure in the` piston chamber 45 to increase until the spring 5| is again enabled to move the application piston and the slide valve 41 to the release position as illustrated in Fig. 1 of the drawings.

When the brake valve handle |00 is moved to lap position the cam |08 carried on the rotary shaft 9.0 is operated to move the stem |04 and the exhaust valve |02 toward the right-hand, thereby unseating the exhaust valve to permit continued discharge of uid under pressure from the brake pipe by way of the discharge Valve passage 2|6, a branch 2|6a of the said passage,

n and through the` valve chamber ||l|` and the at- .izo

|98 leading from the chamber 64 are connected to the atmospheric exhaust port |88 by way of a cavity 226 in the rotary valve 96.

From the foregoing it will be understood that if the brake valve device is allowed to remain in running position or is moved by the engineer to lap position following communication of an unfavorable traffic signal, the automatic train control apparatus vbecomes operative to effect a full service application of the brakes.

If the engineer desires to prevent a train control application of the brakes, however, then at the time the signal indications become unfavorable, as made known by operation of the whistle 21 in the manner hereinbefore described, the engineer must move the brake valve handle |00 to an application position before the chamber 39 in the timing valve device has been sufficiently reduced to permit operation of the double beat valve 30. Upon movement of the brake valve device to the first service position illustrated diagrammatically in Figs. 2 and 3, fluid under pressure is supplied from the recapture reservoir |63 by way of the pipe and passage |62,

tween thc bore 55 and the service reduction reservoir 60, this operation of the recapture device being, however, of substantially no consequence at this time. Similarly, fluid under pressure supplied to the diaphragm chamber 12 acts against the diaphragm 1| to move the double beat valve 14 into its lower seated position, thereby cutting off communication between lthe chamber |94 and the valve chamber 15. The suppression valve device 9 is thus operated to prevent any flow of fluid under pressure from the application piston chamber 45 to the stop reservoir 2 2, which would otherwise occur upon subsequent operation of the timing valve device The application slide valve 41 consequently remains in the release position illustrated in Fig. 1.

Meanwhile, with the lowerv rotary valve 91 of the brake valve device in rst service position, a restricted port 228 formed therein establishes communication between the passages |19 and 202 which is also connected through a restricted passage 228e with the atmosphere, with the result that uid under pressure is vented at a slow rate from the equalizing piston chamber |2| and reservoir |23 by way of the passage |22, cavity in the application slide valve 41, passage |19, cavity 228 and passage and pipe 292 to the reduction limiting reservoir 203, and also by Way of said passage 202 and through the restricted portion |92a of slidevalve passage |92 and passage |93 to theY atmosphere. Y The capacity of reduction limiting reservoir* 203 is such that, upon equalization of fluid pressure therein with that in the equalizing reservoir |23, the consequent reduction of pressure in the equalizing piston chamber |2| causes operation of the vequalizing discharge valve device 93 to vent fluid under pressure from the brake pipe 3 in an amount sufcient to effectV a light application of the brakes for gathering the slack in the train. l

Itwill be noted that with the vbrake valve device in rst service position, fluid under pressure is supplied from the rotary valve chamber through a cavity 229 in the rotary valve 91 and the passage |66 to the valve chamber |21, which contains the maintaining valve |25. Thus in case the'effect of brake pipe leakage in the train is such as to cause reduction of the pressure of fluid in the chamber at a greater rate than that of reduction of pressure in the equalizing piston chamber |2|, the equalizing piston ||9 is temporarily moved to its lowermost position in which the arm I8 of the bell crank lever I6 unseats the maintaining valve |25 to permit the supply of iiuid under pressure from the valve chamber |21 through the chamber to the brake pipe so as substantially to nullify the undesired effect of the brake pipe leakage. In this way there is avoided the possibility that brake pipe leakage might so augment the intended limited amount of reduction in pressure in the brake pipe as to effect a heavy application of the brakes on forward cars prior to gathering of the slack in the train.

It will be noted that fluid under pressure supplied from the recapture reservoir |63 to the diaphragm chamber 12 in the suppression valve device 9 as hereinbefore described is slowly vented to the atmosphere by way of the passage |15, restricted portion |16, valve chamber 84 and past the double beat valve 83 to the chamber B9 in the reduction insuring valve device, and thence through the restricted passage 81. It will thus be seen that if the engineer permits the brake valve device toremain in rst service position until the pressure of fluid in the diaphragm chamber 12 has reduced suiiiciently to permit the spring 11 to return the double beat valve 14 to its upper seated position, iiuid under pressure will be discharged from the application piston Vchamber 45 past said double beat valve to the stop reservoir 24 2 in the manner hereinbefore explained to cause operation of the train Acontrol apparatus for effecting an automatic application of the brakes.

It is to be expected, however, that in the ordinary course of handling the train, the engineer will move the brake valve device from the first service position to service position in time to continue operation of the suppression valve device 9 to suppress a train control application of the brakes. When the handle |00 of :the brake valve device is moved from the first service position to service position a cavity in the rotary valve 91 having a restricted portion 235 is brought into registrationv with the passages |19 and 206, as best shown in Fig. 3 of the drawings, and fluid under pressure is then permitted to vent at a service rate from the equalizing reservoir 203 and piston chamber |2| by way of the passage |22, cavity |80 in the application slide valve 41, passage |19, cavity 235 and atmospheric exhaust passage 206. The passage 202 leading from the reduction. limiting reservoir 293 is likewise connected tothe atmosphere through a passage 233 in the rotary valve 91 and the exhaust port 206. Upon the further reduction in fluid pressure in the equalizing piston chamber |2| thus ei'- fected the fluid at brake pipe pressure in the chamber again moves the equalizing piston ||9 upwardly, thereby operating the bell crank lever I6 to unseat the brake pipe discharge valve H0, so that fluid under pressure is vented from the chamber and consequently from the brake pipe into the discharge passage 2|6.

As shown in Fig. 2 of the drawings, with the `i connects passages 230 and 232,-While a cavity `239 connects the passage |68a. with the passage |66, it being also-noted `that the passage |98 "leading from the recapture piston chamber 64 is vented through a cavity 238 and the atmospheric exhaust port |88. Thus while Huid under pressure vented past the brake pipe discharge valve Iii through the discharge passage 2|6 may` "flow at a restrictedrate throughthe restricted passage 2|1, the branch passage 216s, and past ber 24|, and thence by way of a restricted pact sage 242 and a passage 243 to a. timing reservoir .1 1244, which is thus charged with ud under pressure. A spill-over check valve 246, which is nor- "mally seated bya spring 241, is provided as a means for limiting the build-up in rpressure in the timing reservoir 244, duid under excessive pressure in passage 243 being permitted to escape therefrom through a branch passage 248 and past the `check valve to the passage`232. s

It will be observed that the passage 243 leads `from thetiming reservoir 244 to the chamber 86 within the reduction ensuring valve device' I0, ,from which chamber the fluid may flow past double beat valve 83 and through passage |15 to the diaphragm chamber 12, and also at a slow rate {through the restricted atmospheric passage 81.

"At the same time, fluid under pressure is supplied from the brake; pipe 3 through the passage i ||,2,`the connected chambers |31 and |32 in the cut off valve device-|3|l, which is still in unseated position, and thence through the vpassage |68, the passage |68`a, the cavity 239 in the rotaryvalve, `and the passage |86 to the` diaphragm chamber 12 above the diaphragm 1| of the suppression `valve device 9. The diaphragm1| is thus urged "edownwardly and double beat valve 14 of the sup- `pression valve device is thereby `heldin its lower seated position for preventing operation of the train control apparatus as` hercinbefore explained,

said valve being maintained in this position for a predetermined period of time, due to the eect of iluid pressure'remaining in the timing reservoir 244.

The function of the timing reservoir 244mV causing suppression of a train control application of the brakes for a predetermined interval, as above explained, will enable the engineer to employ an alternative method of effecting a twostage reduction inbrake pipe pressure, if pre- I ferred, which method is well known and consists operating the brake valve `device to service position initially, then to lap position for an interval, and again Yto service position. It will be apparent that'if this method `is used, operation of the train control apparatus will be suppressed duringthe time required for manually effecting `service application of the brakes.

When `the pressure of uid in the equalizing reservoir |23 and the piston chamber l2! has been reduced sufliciently to effect a service application of the brakes, the brake valve device may be moved tolap position, in which the cavity`23| i 70 i cation `between the passages 230 and, 232, sothat in the upper rotary valve 96, maintains communifluid under pressure still being discharged from the brake pipe by the equalizing discharge valve `device will ow through the samekcomrnunications to the suppression valve device'9 as were pointed out in connection with the description of operation in the'service' position of the brake valve device. fWhen the pressure of uid in the brake pipe and in the connected chamber I i has `been reduced sufficiently, the equalizing piston 9 is returned to its normal position as shown in Fig, 1 of the drawings, while the spring i5 is service reduction in brake pipe pressure thus effected results in a service application of the brakes in the usual manner.

Upon the service reduction in brake pipe pressure the pressure of fluid inthediaphragm chamber 82 of the reduction ensuring valve device i8, which is connected with the brake pipe 3 by way of passages ||2 and lla, is correspondingly reduced, and as a result the iiuid pressure in the diaphragm chamber 3| and in the suppression reservoir |84 connected therewith becomes effective to operate the diaphragm 8) for moving the double beat valve 83 to its lower seated posii tion, thereby cutting off the atmospheric combrakes, after traic signal conditions have again become favorable so that the magnet valve device I2 and the timing valve device are again operatedto eiect movement of the double beat valve 3|! to its upperseated position, the handle |88 of the brake valve device is returned to running position. 4With thesis-rake valve device in running `position the brake pipe 3 is again charged with fluid under pressure in themanner hereinbefore described, and the brake controlling valve devices on oars of the train are thereby 'operated in the usual manner te effect the release of the brakes.

From the foregoing itwill be apparent that the Aengineer can suppress an automatic train control. Aapplicatio'r'i of the brakes by moving'the handle of the brake'valve device to first service position promptlyin response to an adverse signal indication and before operation of the timing valve device to vent iluid under pressure from 4the application piston chamber 45. Let it new be assumed that the engineer does not act quickly enough to suppress operation of the tra-in control apparatus, and that as a result the application piston 46 has automatically operated to shift` the application slide valve 41 into the application `position as shown inY Fig ,4 of the drawings. With the train control equipment constructed according to my invention, the engineer may recapture control of the application of the brakes. evenaiter automatic operation of the equipment has been initiatedby movement of the application slide valve to the application position, by quicklyl operating the brake valve device to first service position. 1

If the engineer moves the brake valve handle |80 to first service position immediately after automatic operation of theapplication slide valve j 41, the brake valve device is thereby operated to `eiTect a limited initial` reduction in brake pipe pressure in the manner already described, and at the same time effects supply of fluid under pressure from the recapture reservoir |63 by way of the `pipe-and`pa`s`sage |62, the cavity 221 in permitted to seat the discharge valve H0. The

the upper rotary valve |96, and passage |98 to the piston chamber 64 below the recapture piston |53. The pressure of fluid thus supplied to thepiston chamber 64 moves the piston 63, the stem 66, and the valve element 54 upwardly against the force of the spring 6|, until the seat rib 56 of the valve element engages the gasket 51. i

With the recapture valve element 54 thus seated, communication from the bore 55 to the passage 55 and the service reduction reservoir 63 is cut off, with the result. that, although the application slide valve 41 is in the application position shown in Fig. 4 and communication is established from the equalizing reservoir |23 and piston chamber |2| by way of the passage |22 and through the application slide valve passage 2|4 to the passages 209 and 292, fluid under pressure from the equalizing reservoir can flow only through the passage 292 to the reduction limiting reservoir 293 and through restricted port 228a to atmosphere. As hereinbefore explained, equalization of the pressure in the equalizing reservoir |23 with that in the reduction limiting reservoir 253 results in operation of the brake pipe discharge valve device 93 to vent a limited amount of iiuid under pressure from the brake pipe 3 for effecting a light, slack-gathering application of the brakes.

it will be noted that, with the brake valve device l in first service position and the application slide valve 41 in application position, the lower rotary valve 91 will not be effective to vent fluid under pressure from the equalizingV reservoir by way of the usual communications including the passage |19, since the passage |19 is lapped at the application slide valve.

Fluid under pressure supplied from the recapture reservoir |33 by way ofthe passage I 8E to the diaphragm chamber 12 in the suppression valve device 9, as hereinbefore explained, acts against the diaphragm 1| to move the double beat valve 14 downwardly sothat communication i from the chamber |94 to the valve chamber 15 and the stop reservoir 2 I2 is cut off. At the same time, however, the application slide valve cavity 223 connects the passage 22| with passage'224,

and fluid under pressure is thus permitted to flow from the application piston chamber 45 to the passage 224 and thence to the atmosphere by way of a cavity 249 in the rotary valve 96 which connects the passage 224 with the atmospheric eX- haust port |68 in iirst service position in the brake valverdevice. The pressure of fluid in the slide valve chamber 50 is accordingly effective to maintain the application piston 45 in the application position.

Since as hereinbefore'explained the diaphragm chamber 12 in the suppression valve device 9V is open to atmosphere by way of the passage |15, valve chamber 14 in the reduction ensuring valve device i9, chamber 86, and restricted port 81, the recapture piston chamber B4 is likewise connected with the atmosphere, when the brake valve device is in first service position, by way of the passage |98, rotary valve cavity 221, and passage 86 leading to the diaphragm chamber 12, and it will be apparent that the fluid pressure in recapture piston chamber 64 and in the Vrecapture reservoir |63 connected thereto will after a predetermined interval reduce sufficientlyto permit the spring 6| to move the valve element 54 and the piston B3 downwardly, thereby establishing communication from the bore 55 to the passage 58. With the application slide valve 41 still in application position as shown in Fig. 4 of the drawings, fluid under pressure from the equalizing piston |23 and piston chamber |21 is then free to flow into the service reduction reservoir 69 for completing a fullservice application of the brakes in the manner already explained.

It will thus be seen that an automatic train brake control equipment constructed in accordance with my invention is adapted to permit the engineer to retain control of the brakes by operating the brake valve in response to an adverse traic signal to suppress automatic operation of the train control apparatus toeffect an application of the brakes before such automatic operation has begun, and that in addition the train brake control equipment is further adapted to permit an engineer, who acts-tooV late to suppress automatic operation of the train control apparatus, to recapture atleast some degree of control of the application of the brakes even after the train control apparatus has been set in operation, by operating the brake valve to eiect a two-stage reduction in brake pipe pressure.

WhileV one illustrative embodiment of my invention has been Adescribed in detail, it is not my intention to limit its scope to that embodiment or otherwisel than by the terms of the appended claims. i

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. In a uid pressure brake, in combination, a brake pipe, a reduction in pressure in which is adapted to eiiect an application of the brakes, train control mechanism automatically operative in response to signal indications to effect a preg determined reduction in brake pipe pressure, means preventing suppression of the operation of said mechanism after a reduction in brake pipe pressure has been initiated thereby, manually operab-le means for also effecting reductions in brake pipe pressure, and a recapture means responsive to operation of said manually operable means after a reduction in brake pipe pressure has been initiated by automatic operation of the train control mechanism for limiting the degree of reduc- .l

tion in brake pipe pressure effected by said train control mechanism.A Y Y 2.- In a iiuid pressure brake, in combination, a brake pipe, an equalizing reservoir, discharge valve means operative on a reduction in the pressure of iluid in said equalizing reservoir to vent fluid under pressure from said brake pipe to effect an application of the brakes, train control mechanism automatically operative in response to signal indications to effect a reduction in pressure in said reservoir at a certain rate, manually operable means for eiTecting a reduction in equalizing reservoir pressure at a different rate, and recapture means responsive to operation of said manually operable means after a reduction in equalizing reservoir pressure has been initiated by automatic operation of said train control mechanism for effecting continued reduction in said pressure at said different rate.

3. In a uid pressure brake, in combination, a brake pipe, a reduction in pressure in which effects an application of the brake, train control mechanism automatically operative in response to signal indications to an application position for effecting a reduction in brake pipe pressure of a certain degree, means rendered eiective on operation of said train control mechanism to hold said mechanism in application position,

brake valve means operable manually to con- Y trol the application of the brakes, and recapture 65 eration of said control mechanism for preventing suchautomatic operation thereof, and recapture feoted by said train control lmechanism to a different degree.

4. In a fluid pressure brake, in combination,

" a brake pipe, an equalizing reservoir, discharge lo valve means operative on a reduction in the pressureof fluid in said equalizing reservoir to vent iiuid under pressure from said brake pipe, a rst ,reduotionreservoin a second reduction reservoir,

control train `control mechanism automatically operative iniresponse to an unfavorable traffic signal to establish .communication from said equalizing reservoir to both of said reduction reservoirs, re-

capture means operative to cut off communication from said equalizing reservoir to one of saidA reduction reservoirs, and manually "operative means for controlling operation of said recapture means. 4 i

i 5. In a fluid pressure brake, in combination, a

brake pipe, anequalizing reservoir, a discharge valve operative on a reduction on the pressure of fluid in said equalizing reservoir to vent fluid under pressure from said brake pipe, a first reduction reservoir, a second reduction reservoir, train control mechanism automatically operative in response to anl unfavorable traffic signal to establish communication from said equalizing reservoir to both of lsaid reduction reservoirs, recapture means operative upon an increase in fluid pressure in a chamber to cut off communi- @cation from said equalizing reservoir to one of said reduction reservoirs for varying the ratemofl application of the brakes effected by the train mechanism, and manually operable means adaptedto supply fluid under pressure to `said chamber.

6. In a train control brake apparatus, in combination, a brakev valve device normallyadapted ative in response to movement of said brake valve f device to an rapplication position, during initial for operation to effect an application of the brakes of any desired degree, control mechanism automatically operative Vin response to` adverse traffic signal conditions toeffect a predetermined degree of application of the brakes and to prevent normal operation of said brake valve device, and recapture means adapted to function independently of said control mechanism and operoperation of` said control mechanism `in effecting *anapplication of` the brakes, for causing said Econtrolrnechanismto effect subsequent stages of said application of the brakes in accordance with manipulation of said rbrake valve device.

7. In a train control brake apparatus, in combination, a brake valvedevice manually operative `to `control the application of the brakes, control mechanism automatically operative in accordance withitrafiic conditions to effect an application of the brakes, suppression means operative upon movement of said brake valve `device to a brake application position prior to automatic opmeans` adapted to be operated after automatic operation of said control mechanism in effecting an application of `the brake has begun, for permitting control of subsequent stages of` ,said

brake application through the medium ofsaid `brake `valve device.

ative to control the application of the brakes,

control mechanism automatically operative in accordance with traffic conditions to effect an application. of the brakes, suppression means opervice manually operative to effect an application of the brakes, automatic application valve means having a normal position and operative to an application position in response toa change in signal indications for initiating a train control application of the brakes, means for retaining said automatic valve means in application position and recapture means rendered effective by the operation of said brake valve device, after movement of 4said application valve means to application position and during retention thereof in said application position, for permitting further control of the application of the brakes through the medium of the brake valve device.

i 10..In combination, a brake pipe, a discharge valve mechanism operable to effect a reduction `in the pressure of fluid in said brake pipe to `effect an application of the brakes, train control equnpment, in combination, a brake valve clel control apparatus, for effecting operation4 of said discharge valve mechanism to cause the reduction in brakepipe pressure thereby begun to be limited to a different degree.

11. In a fluid pressure brake equipment, a brake pipe normally charged with fluid under pressure,

train control apparatus automatically operative.

in response to a change in traffic signals to initiate a reduction in brake pipe pressure of a certain degree, a manually operable member, recapture means adapted to be rendered effective upon4 movement of said member for limiting the degree of reduction in brake pipe pressure effected by operation of said train control apparatus, and timing means for rendering said recapture means ineffective after a predetermined interval to prevent continued automatic reduction in the brake pipe pressure to said certain degree.V

12. In a fluid pressure brake, in combination, a brake pipe, a reduction in fluid pressure in which is adapted to effect an application of the brakes, train control mechanism automatically operative in response to a signal indication to an application position for effecting a reduction in brake pipe pressureof a certain degree, brake valve means operable to control the application of the brakes, and recapture means rendered effective by operi ation of said brake valve means, following autopressure initiated by said train control mechanism and then permitting the reduction in brake pipe;

pressurerto be continued to said certain degree.

13. In'a fluid pressure brake, in combination, a brake pipe, a reduction in pressure in which eiiects an application of thebrakes, train control mechanism automatically operative in response to signal indications to an application position for effecting a single-stage service reduction in brake pipe pressure, manually controlled means operative toeffect a service reduction in brake pipe pressure in one or more stages, and recapture means responsive to operation of said manually controlled means, following initial automatic operation of said train control mechanism to said application: position, for so controlling the reduction in brake pipe pressure thus initiated as to split said reduction into two stages.

14. In a fluid pressure brake, in combination, a brake pipe, a reduction in pressure in which effects an application of the brakes, train control mechanism automatically operative in response to signal indications to an application position for eiecting asingle-stage service reduction in brake pipe pressure, manually controlled means operative to effect a service reduction in brake pipe pressure in one or more stages, and recapture means responsive to operation of said manually controlled means, following initial operation of said train control mechanism to. said application position, said-recapture means being operative for partially checking the reduction of brake pipe pressure` thus initiated to permit control of further stages thereof through the medium of said manually controlled means.

15. In a iluid pressure brake, in combination, a brake pipe normally charged with iiuid under pressure, train control mechanism automatically operative in response to signal indications to an application position for effecting a single-stage service reduction in brake pipe pressure, an engineers brake valve device movable to a first service position and to a second service position for normally effecting a two-stage service reduction in brake pipe pressure,rand recapture means operative upon movement of said brake valve device to.

rst service position, `following operation of said train control mechanism to said application position, for at least temporarily diminishing the rate at which the service reduction in brake pipe pressure initiated by thetrain control mechanism is continued. n

16.` In a fluid pressure braking system for a railway train, in combination, a brake pipe normally charged with uid under pressure, an equalizing reservoir normally charged with fluid at brake pipe pressure, a discharge valve mechanism operative upon a, reduction in the pressure of fluid in said equalizing reservoir to vent fluid under pressure from said brake pipe for effecting an application of the brakes, a normally vented reduction limiting. reservoir, a second normally vented `reduction reservoir, train control apparatus automatically operative in response to an adverse traiilc signal to establish communication from said equalizing reservoir to both said reduction reservoirs, recapture valve means operative to cutoi communicationfrom said equalizing reservoir to said second reduction. reservoir, and a brake valve device movable. to a brake application position for effecting4 operation of said recapture valve means, wherebythe rate at which thebrake pipe pressure is reduced by operation of said train control apparatus is controllable lthrough the medium of' said brake valve device;

17. In a fluid pressure brake system for a railway train, in combination, a brake pipe normally charged with. fluid under pressure, an equalizing reservoir normally charged with fluid at brake pipe pressure, a discharge valve mechanism operative upon a reduction in the pressure of iluid in said equalizing reservoir to vent fluid under pressure from said brake pipe for effecting an application of the brakes, a normally vented reduction limiting reservoir, a second normally vented reduction reservoir, train control apparatus automatically operative in response to an adverse traiic signal to establish communication from said equalizing reservoir to both said reduction reservoirs, a normally open valve operative to cut off the communication Vbetween said equalizing reservoir and` said second reduction reservoir, a movable abutment subject to the pressure of fluid in a chamber for operating said valve, and a brake valve device movable to a brake application position for supplying fluid under pressure to said chamber. l i .1

18. In a fluid pressure braking system for a railway train, in combination, a brake pipe normally charged with iluid under pressure, an equalizing reservoir normally charged with iluid at brake pipe pressure, a discharge valve mechanism operative upon a reduction in pressure of fluid in said equalizing reservoir to vent fluid under pressure from said brake pipe to eiect an application of the brakes, train control apparatus automatically operative in response to an adverse trame signal to vent fluid under pressure from said equalizing reservoir, recapture valve means operative to diminish the amount of fluid under pressure vented from said equalizing reservoir by automatic operation of said train control apparatus, and a brake valve device movable to a brake application position for eifecting operation of said recapture Valve means, whereby the application of the brake initiatedby operation from said train control apparatus is controllable through the medium of said brake valve device.

19. In a fluid pressure braking system for a railway train, in combination, a brake pipe normally charged with fluid under pressure, an equalzing reservoir normally charged with iluid at brake pipe pressure, a discharge valve mechanism operative on a reduction in the pressure of fluid in said equalizing reservoir to vent fluid under pressure fromthe brake pipe for eiecting an application of the brakes, a normally vented reduction limiting reservoir, a second normally vented reduction reservoir, train control apparatus automatically operativein response to an adverse traffic signal to establish communication from said equalizing reservoir to both said reduction reservoirs, a valve operative to control communication between said equalizing reservoir and said second reduction reservoir, a spring normally maintaining said valve open, a movable abutment operative upon an increase in pressure of fluid in a chamber for closing said valve, manually operable means for supplying fluid under pressure toI said chamber, and a restricted atmospheric communication adapted to permit gradual escape of iiuid under pressure thus supplied to said chamber, whereby after alpredetermined interval said spring again becomes effective to open said valve.

20. In a iiuid pressure brake system for a railway train, in combination, a brake pipe normally charged with fluid under pressure, an equalizing reservoirnormally charged with iiuid at brake pipel pressure, adischarge; va1vemechanism operative on a reduction in the pressure of uid in said equalizing reservoir to vent iluid under pressure from said brake pipe to effect an application of the brakes, a train control apparatus automatically operative in response to an adverse trafficsignal to vent fluid under pressure from said equalizing reservoir, recapture valve means subject to and operative upon an increase in the pressure of fluid in a chamber for limiting the amount ofv fluid under pressure vented from the equalizing reservoir by automatic operation of `said train control apparatus, a recapture reservoir, and manually operable brake valve means having one position for maintaining said recapture reservoir charged with fluid under pressure, and movable to a brake application position for supplying fluid under pressure from said recapture reservoir to said chamber, whereby When said train control apparatus is automatically set in operation the rate at which brake pipe pressure l is reduced is controllable through the medium of said brake valve means.

bination, an application valve mechanism automatically operative from a release position to an application position in response to an ad- `verse signal indication for effecting an applicaof an automatic application of the brakes initiated- `by said application valve mechanism after movement thereof to said application position, and a brake valve device manually' movable to a brake l the brakes of a certain degree, a suppression valve applicationr position for `supplying fluid under pressure to both said chambers.

22.,In a train: control brake system, in combination, an application valve mechanism automatically operative from a release `position to an application position in response to an adverse `signal indication for effecting an application of device operative on an increase in fluid pressure in a chamber toprevent subsequent movement of `said application valve mechanism to said application position, a recapture valve mechanism operative upon an increase in fluid pressure in another chamber to limit the degree of an automatic application of the brakes initiated by said fjapplication valve mechanism after movement 55` thereof to said application position, a rectapture reservoir adapted tolbe normally charged with fluid under pressure, and a brake valve device manually movable to a brake application position for supplying fluid under pressure from. said recapture to both of said chambers.

23. In a train control brake system, in combination, a brake pipe, an application valve mechanism automatically operative from a release position to an application position in response to an adverse signal indication for venting fluid under pressure from said brake pipe at a certain rateA for effecting application of the brakes, a suppression valve device operative upon an increase in fluid pressure in a chamber to prevent subsequent `movement, of said application valve mechanism to application position, a reservoir, and a brake valve device operative in a running position to maintain said reservoir charged With uid under pressure, said brake valve device being operative when moved to a first service position to supply fluid under pressure from said reservoir to said suppression valve chamber and when moved to a second service position to supply iiuid under pressure from said brake pipe to said chamber.

24. In a fluid pressure brake, in combination, a brake pipe, a reduction in pressure in which is adapted to effect an application of the brakes, train control mechanism automatically operative in response to a change in a signal indication to effect a reduction in brake pipe pressure, recapture valve means operative to cause said reduction in brake pipe pressure to be effected in two stages after the reduction in brake pipe pressure has been initiated by operation of saidV train control mechanism, and means operable manually for effecting the operation of said valve means.

25. In a fluid pressure brake, in combination, a brake pipe, a reduction in fluid pressure in which is adapted to effect an application of the brakes, a normally charged equalizing reservoir, discharge valve mechanism operative in response to a reduction in fluid pressure in said equalizing reservoir to effect a corresponding reduction in uid pressure in said brake pipe, a reduction reservoir volume, train control apparatus automatically operative in response to a change in a. signal oondition to vent fluid under pressure from said equalizing reservoir into said reduction reservoir volume, recapture means operative to reduce said reduction reservoir volume, and manually controlled means for effecting the operation of said recapture means.

26. In a iluid pressure brake train control eequipment, in combination, a brake pipe, an

equalizing reservoir, a discharge valve mechanism operative on a reduction in fluid pressure in said equalizing reservoir to vent uid under pressure from said brake pipe, a brake valve device manually operable to vent uid under pressure from said equalizing reservoir through one communication, brake application valve means having a normal position and automatically movable therefrom on a change in traffic signals to an application position for cutting off said communication and for establishing an additional communication through Which uid under pressure is vented from said equalizing reservoir, and recapture means responsive to manipulation of said brake valve device for limiting the venting of fluid under pressure through said additional communication.

27. 'In a fluid pressure brake train control equipment, in combination, a brake pipe, an equalizing reservoir, a discharge valve mechanism operative on a. reduction in fluid pressure in said equalizing reservoir to vent fluid under pressure from said brake pipe, a brake valve device manually operable to vent Huid under pressure from said equalizing reservoir through one communication, brake application valve means having a normal position and automatically movable therefrom on a change in traffic signals to an application position for cutting oif said communication and for establishing an additional communication through which fluid under pressure is vented from said equalizing reservoir, and recapture means operative to control the flow of fluid under pressure from the brake pipe through said additional communication in accordance with manual operation of said brake valve device.

28. In a iiuid pressure brake system for a railway train, in combination, a brake pipe normally charged withfluid under pressure, a brake valve device normally adapted for operation to effect a reduction in brake pipe pressure of any desired degree, train control mechanism automatically operative, in response to communication of an adverse traffic signal, to initiate a predetermined degree of reduction in brake pipe pressure and to render said brake valve device ineiective for said normal operation, and recapture means Operative in response to manipulation of said brake valve device to control further stages of a reduction in brake pipe pressure as effected by 1' continued operation of said train control mechamsm.

29. In an automatic train control brake equipment for a railway train, in combination, a brake pipe normally charged with uid under pressure, a brake valve device normally adapted for operation to effect a reduction in brake pipe pressure of any desired degree, train control mechanism automatically operative, in response to communication of an adverse trafc condition, to initiate a predetermined degree of reduction in brake pipe pressure and to render said brake valve device ineiective for said normal operation, and recapture means operative in response to manipulation ofsaid brake valve device, after automatic opera'- Y tion of the train control mechanism has begun,

to control the rate at which the reduction in brake pipe pressure is effected by operation of said train control mechanism.

30. In an automatic train control brake system,

in combination, a brake pipe normally charged Withfluid under pressure, an equalizing reservoir normally charged With uid under pressure, an equalizing piston subject to the opposing pressures of iiuid in lthe brake pipe and in said ,equalizing reservoir, a normally closed discharge valve operative by said piston to vent fluid under pressure fromA the brake pipe in accordance with reduction in equalizing reservoir pressure, a train control application valve mechanism automatically operative in response to an adverse trafc signal to vent fluid from said equalizing reservoir for causing a service application of the brakes, and a normally closed maintaining valve operative by said equalizing piston to supply uid under pressure to the brake pipe inrtlfn'e eventofreduction of pressure infsaid brake pipe below` that inl said equalizing reservoir; whereby. the train control: reduction in brake pipe pressure'is prevented from exceeding the desired rate.

' 31. In ailuid` pressure,V brake andtrain control system, in combination afbrake pipe, an equalizing reservoir; anv equalizing` discharge valve mechanism operative upon a reduction in pressure in the equalizing reservoir for venting iiuid.

under pressure'from the brake. pipe, a reduction reservoin an application valve device operative in response to an,y adverse signal indication for establishing communication from the equalizing reservoir` to the reduction` reservoir, a recapture valve device for controlling communication from theequalizing` reservoir tothezreduction4 reservoir, and a manually operable valve. device for controlling the operation of,` said'recapture valve device.

32';` In an' automatic 'uidi pressure brake and train control equipmentV of the class involving a brake: pipe,. a. brake Valve` device normally operable'by manual contralto. effect. reduction of the pressure of fluid'. in said brake. pipe in any number of stages for eiectingfi abrake application of a desired degree, and trainl control mechanism automatically operative, in response to communication ofv an adverse traiiic signal, to take over control of said brakevalve; device for initiating a predetermined degree of.` reductioni inbrake pipe pressurein a single stage While. rendering said brake valve device ineffective for said normal operation, in combination,` ai. recapture valve adapted for cooperation with said' train control mechanism tol prevent, an'. automatically initiated train control. reduction: in. brake pipe pressure from exceeding a desired rate,. and. iiuid pressure responsive meansicontrolled by manipulation of said brake valve device toractuate said recapture valve, whereby thev engineer may regain' atleast partial control' ciy anaut'omatic application ofithe brakes being effectedthrougln the medium of thetrain control mechanism.-A

CLYDE C; FARMER. 

